Electric heater



March 8,1927.

. 1,620,296 J. E. SEDERHOLM ELECTRIC HEATER Filed July 5. 1926 2 Sheets-Sheebl f/vrzA/rb/r JOHN L". JEDE/W/QLM Patented Mar. 8, 1927.

UNITED STATES Parent oFicE;

JOHN E. SEDERHOLM, OF ST. PAUL. MINNESOTA, ASSIGNOR T AMERICAN HOIST &

DERRICK COMPANY, A PARTNERSHIP WASHBURN, OF ST. PAUL, MINNESOTA.

COMPOSED OF F. J. JOHNSON AND VI. 0.

ELECTRIC HEATER.

Application filed July 3,

This invention relates generally to improvements in electric heaters, of a type in which stationary and movable cores are employed, and in which provision must be made for placing a very heavy movable core piece 0 :er and upon a stationary core, after nitroduction of a work piece or ring, and in which the movable core must be alternately positioned to permit unobstructed introduction and removal of the work. This case is an improvement over my allowed application, Serial No. 730,091, allowed October 22, 1926.

The objects are to provide an improved structure for pendcntly supporting the movable core, for a minimum movement to and away from working position; to provide means for propelling the core-supporting means, and for guiding the supported core during translation; to provide means for raising and lowering the movable core on its support or hanger; 10 provide compact base and supporting structures for both cores, so arranged as to ermit; and obtain translation of the movable core, to project through a portion of the frame, when moved in direction of greatest length of both cores, and thus to permit unobstructed placement and removal of the work; to provide for a minimum movement ot the movable core, both horizontally and vertically; and to provide av cheap structural iron frame wherein the base elements act to clamp the lamination of a stationary magnetic core.

l aturcs of the invention include the structural details of all portions of the device, wherein cheapness, compactness, conibiued with convenience of manipulation, re sults.

In the accompanying drawings forming part of this specification,

Figure l is a vertical sectional view of the apparatus in operative position;

Figure 2 is a sectional plan on the line 22 of Figure l: and

Figure is a vertical sectional view on the line 3-3 of Figure 1.

The base comprises two parallel channel irons 1, disposed with their concave sides facing outwardly, and thus providing flat inner faces for engaging and clampingly sccuring the laminations of a U-shaped stationary core, between them. Bolts 2, placed 1926. Serial No. 120,432.

at each end and at the bottom are employed. The arrangement of these bolts virtually provides a socket into which the lower end of the core 3 is inserted, the bolts being then lightened to secure the parts. Additional bolts secure the laminations of the core at the upper end of each leg. Two upstanding legs are provided, front and rear, respectively designated a and 5, and a work space is provided therebetween.

To each iron 1 at the rear is secured, as

by welding, an uupright channel iron 6, these irons having their concave sides also facing outwardly. Across the top of the irons (i is secured a transverse bar 7, thus completing the formation of an open rectangular frame, at the rear of the stationary core. About the rear leg 5 of the stationary core is titled a rectangular horizontal coil 8, built up in layers, separated by asbestos insulation. The inner side of the coil has a facing ot' insulating'strips 9. Asbestos insulation is provided upon the top surface of the horizontal member of the core, between the legs, as a work rest, and covers the entire surface. crosswise. and lengthwise between the insulating facing, and the trout leg of the core.

Secured centrally to the bar 7, as by welding, and extending horizontally forwardly centrally over the stationary core. is an T- bi-ain 2.3, Forminga track, longitudinal with respect to the core, movable laminated (:orc 2b is suspended from this track by means of a carriage and hanger, said carriage being guidingly supported for translation on the track, all as now to be describod. I i

The carriage frame 530 generally crosscctioi'udly U-shapcd, and is inverted, and has journaled Cl'OsSWiSB between its opposilo depending sides 31, two flanged rollers 32. "lhc journal :33 of one of the rollers is fixed thereto and has a crank extension 34, by means of which the roller can be rotated to act as a tractor for translating the carriage. The horizontal portion of the carriage above the rollers has a centrallv disposed depression or socket 35. Encircling the carriage and track is a hanger frame 36, having a power screw :37 in threaded engagement through its top member 38. The hottom of said screw rests in the socket 35 and thus pivotally supports the ban er for vertical power adjustment. A han -wheel 41 of relatively large diameter operates the screw.

The hanger frame, as well as the carriage, are cast, and each is properly reinforced for heavy duty. The bottom oflthe hanger frame provides what may be termed a socket for the reception of the laminated movable core 26, which is connected by its middle portion therein, as by bolts 42. The whole suspended structure is balanced. The laminations of the movable core are secured by bolts 45. Asbestos insulation is shown at 46. Forwardly extending members 50 guide the core at the rear, and prevent rotation thereof on the power screw as a pivot, and engage and guide said movable core at all positions thereof. The forward outer end,

of the track, beyond the hanger, is provided with a cross-member 52, adapted to engage or be engaged by the hanger at both sides to limit its outward movement, to cause the ends of the movable core to register with the ends of the stationary core.

As thus arranged, the rear end of the movable core, as well as the corresponding end of the stationary core, are spaced only a short distance from the open frame. The hanger is also spaced at such a minimum distance forwardly of the frame, as to permit a sufficient rearward movement thereof, be-

fore engaging the frame, as will dispose the front end 48 of the movable core, substantially vertically above the front side of the insulating facing of the coil. It will be noted that this movement is in a direction longitudinally of both cores, and is of a minimum length, for a complete clearance of the work space, to permit unobstructed placement or removal of the work. It will also be noted that the upper side of the movable core is spaced only a relatively short distance from the lower side of the track, so that a slight upward movement only of the movable core is necessary to disengage it, preparatory to its rearward movement.

I claim as my'invention:

1. A device of the class described, comprising a stationary core, an open frame arranged transversely at one end of said core, a track supported by said frameabove the core, a movable core, and means translatably supporting the core upon the track for movement longitudinally of the stationary core and track, through the frame.

2. A device of the class described, comprising stationary and movable cores, an open frame disposed transversely at one end of said stationary core, a track overhanging the stationary core, lengthwise with respect thereto, a carriage having rollers guidingly engaging the track and having a socket in its upper side, a hanger frame carrying a screw resting within the socket, said movable core aeaaaee attached to the hanger and disposed horizontally of the track, therebelow, for translation through the frame.

3. A device of the class described, comprising a stationary core, an open frame transversely disposed at one end thereof, a track extending forwardly over the stationary core from the top of the frame, a car riage translatably guided upon the track, a hanger frame pivotally supported upon the carriage, encircling carriage and track, and a core piece attached to said hanger and held positioned for translation longitudinally therebelow, through the frame.

4. A device of the class described comprising a stationary core, an open frame at the rear thereof, a track, upon said frame longitudinally over the core, a carriage having rollers guidingly engaging the track, a crank for rotating one of the rollers as a tractor wheel, said carriage having a central. socket, a hanger having a power screw, with its lower end resting within the socket, said frame having portions disposed at opposite sides of said carriage and track and extending tlierebelow, and a movable core attached at its middle between the downwardly extending portions of said hanger frame, said screw acting to pivot the hanger upon the carriage to forcibly raise and lower the hanger frame.

5. A frame structure for the purpose described, having a base comprising two spaced parallel base-forming channel irons, bolts traversing said irons and forming an open socket therebetween, a vertical channel iron welded to the end of each base iron, said irons spaced to permit translation of a pole piece therethrough, and cross-connected at the top by a bar, a track beam extending above and longitudinally parallel with the base channels, vertically and centrally thereover.

6. A device of the class described, having a base comprising two spaced parallel base forming channel irons, bolts traversing said irons and forming a skeleton socket therebetween, a vertical channel iron welded to the end of each base iron, said irons spaced to form an open frame to permit translation of a pole piece therethrough, and cross-connected at the top by a bar, a track beam extending above and longitudinally parallel with the base channels, vertically centrally thereover, the rear end of the socket being immediatel adjacent the frame.

7. A devlce of the class described having a base, an open frame secured vertically rearwardly at one end of said base, a track extending forwardly from the top of said frame parallel with the base and centrally vertically thereover, a U-shaped core stepped in. the base frame, extending thereabove and centrally related to the frame opening, and providing a work space and a movable core II- stationary core nearest the open frame, disposed immediately adjacent said frame, and

a movable core translatably suspended upon the track member for vertical adjustment,-

and having its top and rear ends s aced relatively short distances respectively rom track and frame when in operative position upon the stationary core,.and adapted to be translated rearwardly through said frame in direction lengthwise of both cores, and when so translated to its rearward limit, to have its forward end disposed substantially in vertical alinement with the forward side' of the coil, to permit unobstructed removal of the work.

In witness whereof, I have hereunto set my hand this 28th day of June, 1926.

JCHN E. SEDERHOLM. 

